Answers

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  Why should an arch be reserved during the construction of corrugated culverts?

  Corrugated culverts buried in ordinary soil foundations often experience a certain degree of subsidence after a period of time, and the subsidence is usually greater in the middle of the pipe than at both ends.
  Therefore, the corrugated culvert pipes laid under the embankment should have an upward pre-camber in the middle. The pre-camber is determined by a comprehensive consideration of factors such as the potential settlement of the foundation, the longitudinal slope of the culvert bottom, and the height of the fill. It is usually 0.3% to 1% of the pipe length, and the maximum is no more than 2%, to ensure that no depression or landslide occurs in the middle of the pipe.

  
  
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  Hi, I'm sourcing steel rebar, HRB400 grade. Diameter 8mm, 12mm, 16mm, length 12 meters. Need 200 to 500 metric tonnes FOB China. What's your rock-bottom price, delivery time, and can you send samples?

  We have contacted you via email and website message regarding your required HRB400 steel bars (8/12/16mm x 12 meters). Based on your purchase quantity of 200 to 500 metric tons and FOB delivery terms at major Chinese ports, our professional purchasing team will directly calculate costs for you and provide the most competitive comprehensive solution.
  
  Please confirm the following information: Precise purchase quantity: Please provide your planned minimum order quantity (e.g., 300 tons or 500 tons) so we can give you the most accurate quote.
  Target port of shipment: Please inform us of your preferred major Chinese ports (e.g., Tianjin Port, Shanghai Port, Qingdao Port, etc.) so we can calculate the accurate FOB costs.
  Sample requirements: We can immediately coordinate and send standard samples from our partner steel mills' inventory according to your requirements. Please provide your detailed mailing address and contact information.
  Upon receiving the above information, our team will send you a formal quotation via email as soon as possible, and detailed delivery date.
  
  You can reply to the email or provide additional information through the official website's message board.

  
  
• 
  What's the difference between wire rod and rebar?

  Appearance
  Wire Rod: Smooth like noodles, usually less than 10mm in diameter, transported in coils, occasionally with a slight oxide scale on the surface.
  Rebar: A tough guy with barbs all over, with regularly raised horizontal and vertical ribs on the surface, mostly over 12mm in diameter, stored in straight strips.
  
  Performance
  Flexibility: Wire rod can be easily bent 360 degrees, suitable for deep processing; rebar is more likely to break than bend, maintaining a straight shape.
  Strength: Rebar has higher grip strength due to its surface texture, as stable as a rock in concrete; wire rod prioritizes ductility.
  Processing Method: Wire rod is often drawn into thinner wires, while rebar is mostly cut directly for use.